Re: [Paddlewise] volume and safety

The person we need here is John Winters; he's said that stability
is one of his favorite topics.  He's also explained broaching in a
way that is easy for me to understand.

Gerald Foodman wrote:

> Bill Hanson wrote
> >There is no inherent safety in large volume boats, as such. Some boats are
> >better designed for some purposes, that's all. My subjective impressions
> >have been that shorter boats are easier to control in following seas, **all
> >other things being equal
>
> I don't want to compare large volume boats to narrow boats in following sea
> conditions.  Rather the comparison is between narrow boats and SLIGHTLY
> wider ones.  I mean those with a bit more, but not too much, stability.
>

There are probably more important factors in stability than just the beam
or volume.  The hull shape and the difference between the initial and
secondary stability is important.  I recently paddled (in a pool) the latest
boat from Boreal Designs, the Ellesmere.  It is a Greenland style boat
with a hard chine hull.  I own a Solstice GTH and have played with a GTS.
These boats are very different.  The Ellesmere is narrow, around 21 or 22
inches (the latest Sea Kayaker mag has a photo and details) and is
comparable in some ways to the GTS.  However, the difference in stability
is notable.  The GTS has good initial stability and fair secondary stability
that allows you to lean the boat over for a turn. However, the Ellesmere has
good initial stability and astounding (for a narrow boat) secondary stability.
It is not the magnitude of the righting moment that is striking, but the fact that
the Ellesmere can sit on edge very easily.  The GTS is tricky to keep on edge
in that once on edge you aren't balanced well (most boats I've paddled are
like this, but I've tried few hard chine boats) and you have to actively maintain
the balance.  The Ellesmere seems to like sitting on edge - a little knee
pressure and you're up and can stay there!  Note that I'm comparing these
boats empty - loaded for touring could yield different impressions.  By the
way, my guess is that the Ellesmere is a smaller volume boat than the GTS.

I love my GTH for touring, but for playing in rougher conditions, I'd like
to try the Ellesmere.  Even though it's a narrower boat, its stability
characteristics, coupled with it's rocker and manouverability make me
believe it would be fun and reliable.

I'll second the comments already made that stability is secondary to
broaching characteristics in the conditions you've described as
the target environment for your boat usage.


>
> The reason I wondered about volume and the likelihood of capsize is that
> with a bit more stability, especially with the chine as in the MAX, a non
> professional like myself will lean  more confidently and be less likely to
> lean either too much or too little.  The boat would be more forgiving of
> mistakes.

I think the only way to determine  the suitability of a boat for yourself
would be to ignore the numbers and try them in the water.  I don't think
that you can safely generalize on the handling characteristics based on
a few dimensions like beam, volume etc.

>
> John Myers wrote:
> >I recently talked with Cam Broze about the Express, Max and M-2. He puts
> >the M-2 in the                                       skinny boat category,
> >more likely to capsize in rough conditions. His personal favorite is the
> >Coaster which is not surprising since this is his own design. Somehow the
> >canard that "narrow" is seaworthy and "wide" is not has become a widely
> >held belief but one which I think is invalid. My personal bias against wide
> >kayaks is based more on sluggish performance and sloppy fit. Evidence seems
> >to suggest that very narrow boats [less than 22"] are more likely to
> >capsize even  in the hands of an expert.
>
> I think that you may be correct.  But I have found no experts to agree.
>

Shouldn't that canard be "wide is seaworthy and narrow isn't"? - at least that's
what I usually hear.  Wide usually means higher initial stability.  Initial stability
means on flat water - on waves that translates into an overturning moment
rather than a righting one.  Beginners judge a boat by its initial stability since
it feels more stable on flat water.  Experienced paddlers aren't as quick to
judge.  As far as narrow boats capsizing in the hands of experts - could it be
that they push the limits more?

Too many variables, not enough time to evaluate them all.

Mike



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